Table 2.
Mean (± SD) retinal nerve fiber layer thickness measurements (µm) obtained by optical coherence tomography at different times during follow-up.
| Time | N* | Glaucoma | Controls | P |
|---|---|---|---|---|
| 0 | 150 | 75.0 ± 9.8 | 90.6 ± 8.0 | <0.001 |
| −2 years | 136 | 79.7 ± 9.0 | 90.4 ± 7.8 | <0.001 |
| −4 years | 108 | 81.3 ± 9.9 | 91.0 ± 8.0 | <0.001 |
| −6 years | 90 | 83.6 ± 8.0 | 91.2 ± 7.6 | 0.002 |
| −8 years | 52 | 86.3 ± 8.2 | 91.4 ± 7.6 | 0.021 |
Time 0 corresponds to the date of conversion to the earliest detectable visual field defect in glaucoma cases and last follow-up date for controls. Negative time values correspond to years before time 0.
*
N corresponds to the total sample size (matched cases and controls) available at each time point.